Vapor pressurized hydrostatic drive

ABSTRACT

A hydrostatic drive system generally of the type wherein vapor is alternately directed into one of two reservoir tanks so that working fluid in that tank is forced out of the tank by pressure of the vapor and through a fluidic motor to generate a mechanical output before it returns to refill the other tank. When the first tank is substantially depleted, the vapor pressure is directed into the refilled tank so that fluid from that tank now flows through the motor to refill the first, now depleted, tank. In one embodiment, cyclic pressure generated by a vapor generator forces fluid cyclically through an AC fluid motor. In another embodiment, heat from the working fluid is employed to generate the vapor pressure and reduce the temperature of the working fluid passing through the motor. In a further embodiment, the fuel serves as the working fluid and the vapor from the refilling tank is combusted to provide heat to convert the fuel from its liquid to vapor state. In another embodiment, the combustion gases are combined with the vapor so that, when water is the working fluid, the water vapor in the combustion gases serves as make up working fluid. In a further embodiment, heat from working fluid on its way to the motor is transferred to other working fluid in a second system to drive a second motor. Further aspects of the invention are set forth below.

United States Patent [191 McAlister [111 3,830,065 [451 Aug. 20, 1.974

[ VAPOR PRESSURIZED HYDROSTATIC DRIVE [76] Inventor: Roy E. McAlister, 52 85 N. Red

Rock Dr., Phoenix, Ariz. 85018 [22] Filed: Feb. 28, 1972 [21] Appl. No.: 229,764

Related US. Application Data [62] Division of Serv No. 58,934, July 28, 1970.

[52] US. Cl. 60/670 [51] Int. Cl. F0lk 25/00, FOlk 27/00 [58] Field of Search 91/4; 417/379; 60/670, 60/671 [56] References Cited UNITED STATES PATENTS 228,555 6/1880 Pike 91/4 1,626,556 4 1927 Ridgway 91 4 x 2,688,923 9/1954 Bonaventura. 417/379 2,849,987 9/1958 Shafer 91/4 X 3,100,965 8/1963 Blackburn 91/4 X 3,608,311 9/1971 Roesel, Jr. 60/1 X Primary ExaminerEdgar W. Geoghegan Assistant ExaminerAllen M. Ostrager Attorney, Agent, or Firm-Cushman, Darby & Cushman [5 7] ABSTRACT A hydrostatic drive system generally of the type wherein vapor is alternately directed into one of two reservoir tanks so that working fluid in that tank is forced out of the tank by pressure of the vapor and through a fluidic motor to generate a mechanical output before it returns to refill the other tank. When the first tank is substantially depleted, the vapor pressure is directed into the refilled tank so that fluid from that tank now flows through themotor to refill the first, now depleted, tank. In one embodiment, cyclic pressure generated by a vapor generator forces fluid cyclically through an AC fluid motor. In another embodiment, heat from the working fluid is employed to generate the vapor pressure and reduce the temperature of the working fluid passing through the motor. In a further embodiment, the fuel serves as the working fluid and the vapor from the refilling tank is combusted to provide heat to convert the fuel from its liquid to vapor state. In another embodiment, the combustion gases are combined with the vapor so that, when water is the working fluid, the water vapor in the combustion gases serves as make up working fluid; In a further embodiment, heat from working fluid on its way to the motor is transferred to other working fluid in a second system to drive a second motor. Further aspects of the invention are set forth below.

36 Claims, 18 Drawing Figures PATENTEO M1620 I974 3380.065 sum ear 9 PATENTEB M1920 m4 snmanr 9 (b4 rzaL-- PATENTEnwsao I974 3.880.085

' saw 5 or 9 All PHENTED M20 1914 SHEET 7 OF 9 This is a division, of application Ser. No. 58,934 filed July 28, I970.

BRIEF DESCRIPTION OF THE PRIOR ART AND SUMMARY OF THE INVENTION The invention relation to a vapor pressurized hydrostatic drive for converting heat into mechanical motion.

Over the past few centuries, one of the continuing goals of technology has been the improvement of systems for converting energy in the form of heat into mechanical motion. The widely employed conventional steam engine and internal combustion engine are the products of this continued effort. Neither of these engines is, however, completely staisfactory. Both are complicated heavy machines whose efficiency in accomplishing the energy conversion is normally quite low. The internal combustion engine produces pollutants which are both dangerous and obnoxious.

One promising heat conversion apparatus which has been developed includes a tank containing a working fluid and a fluid motor operatively connected to the tank so that when heat is added to the system a pressure is generated on the fluid in the tank which forces it out the tank and through the motor, thus generating a mechanical output. A second tank can be added to the system so that the fluid after passage through the motor can refill that tank. When the second tank is full, pressure can be generated on the fluid in that tank to force fluid flow out of the second and through the motor to refill the first. Such systems are shown, for example, in

Pike U.S. Pat. No. 228,555 and Parish U.S. Pat. No.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I shows a first embodiment of the invention with a DC. fluid motor,

FIG. 2 shows a further embodiment with an A.C.

fluid motor,

FIG. 3 shows a device for injecting fluid as fine'droplets into a steam generator,

FIG. 4 shows a further embodiment of the invention wherein the fluid to be varporized is drawn from the reservoir tank,

FIG. 5 shows a further embodiment of the invention 2 absorbs heat from the working fluid in the tank being refilled,

FIG. 9 shows a further embodiment of the invention in which a porous steam storage bed absorbs heat from the working fluid in the tank being refilled,

FIG. 10 shows another embodiment of the invention wherein a portion of the heat in the working fluid is recovered and employed to generate a mechanical output,

FIG. 11 shows another embodiment in which heat in the fluid on its way to the fluid motor is transmitted to fluid leaving the fluid motor on its way to refill'one of the reservoir tanks,

FIG. 12 shows another embodiment of the invention wherein a portion of the working fluid is evaporated from the heat exchanger to cool the working fluid,

FIG. 13 shows another embodiment of the invention in which the working fluid which is vaporized absorbs heat from the working fluid in the tank being refilled,

FIG. 14 shows a further embodiment whereby heat in the working fluid on its way to the fluid motor is transferred to working fluid in a second system to cause vaporization of that second fluid and operation of a second fluid motor,

FIG. 15 shows an embodiment of the invention wherein two systems are connected together to a single shaft,

FIG. 16 shows an embodiment of the invention in which each reservoir includes fluids separated by an impermeable barrier which is able to move within the reservoir.

FIG. 17 shows another embodiment of the invention in which the heat generated by fuel being combusted is employed to generate vapor pressure to force the fuel through a fluid motor and into the combustion chamber,

FIG. 18 shows a modification of the embodiment of FIG. 17 in which the vapor pressure in the reservoir tank is generated by vaporizing a portion of the fuel in that tank.

DETAILED DESCRIPTION OF THE DRAWINGS Reference is now made to FIG. 1 which illustrates a hydrostatic drive system 18 suitable for use with a DC. fluid motor. In this embodiment, as in many of the other embodiments of the invention, as discussed in detail below, vapor is alternatively directed into one of the two reservoir tanks 20 and 22 so that the working fluid in that tank is forced out of the tank by the pressure of the vapor, and through a conventional fluidic motor 38 to generate a mechanical output before it returns to refill the other tank. When the first tank is subthe refilled tank so that the fluid from that tank now flows again through motor 38 to refill the first, now depleted, tank.

In FIG. 1, a suitable reservoir 24 of a fluid such as water is connected to a conventional phase converter or boiler 26 which converts the fluid from a liquid to a vapor phase. This conversion may be accomplished by burning a suitable fuel such as a hydrocarbon adjacent boiler 26 so that the generated heat changes the phase of at least a portion of the fluid in boiler 26. Any other suitable arrangement for generating the vapor which is employed to impart motion to the working fluid can be employed. The vapor pressure output of boiler 26 is directed to either reservoir tank or tank 22 via master valve 28 which may be a conventional solenoid valve or any other suitable type of conventional mechanism. As depicted schematically in FIG. 1, valve 28 is operated by a suitable control apparatus 30, which alternately causes valve 28 to direct the vapor pressure generated by boiler 26 to reservoir tanks 20 and 22. Control 30 may be mechanically or otherwise linked to the fluid motor 38 so that the position of the valve 28 is responsive to the physical position of the rotating part of fluid motor 38. Alternately, control 30 may include means for sensing the fluid level in tanks 20 and 22 and switching the tank which is being emptied whenever the fluid in a tank is detected below a certain predetermined level.

Assuming for the purposes of describing the operation of the embodiment of FIG. 1 that control 30 has shifted valve 28 to a position such that the vapor pressure generated by boiler 26 is transmitted into tank 22 as depicted, then that vapor pressure pushing the fluid in tank 22 causes working fluid to exit from the bottom of tank 22 and to flow through motor 38 via one way check valve 32. Valve 32, as well as the other check valves in this and the other embodiments set forth below, permit fluid flow in one direction but prevent it in the other. These valves may be of any suitable type and are well known in the art. After passage through motor 38, the moving fluid passes through check valve 34 and enters tank 20. The differential between the pressure of the fluid exiting from tank 22 and the fluid exiting from motor 38 prevents fluid from flowing back through check valves 36 and 38. An exhaust valve 40, which also is shown under the control of apparatus 30, is vented to the atmosphere during this time so that the fluid can freely enter chamber 20. Valve 42 at the same time is closed to prevent the loss of thevapor pressure generated by the flow of vapor into tank 22 via valve The cyclic venting of tanks 20 and 22 to the atmosphere results in a gradual reduction in the quantity of working fluid in the system. Reservoir 24 provides some make-up since some of the vapor directed into the tanks condenses therein and is thus added to the supply of working fluid. However, it may be desirable to provide some suitable arrangement for automatically or otherwise replenishing the working fluid from time to time.

When tank 22 has been depleted or substantially depleted, control mechanism shifts the position of valve 28 so that the vapor pressure generated by boiler 26 is now directed into tank 20 and begins to force the fluid which has refilled it out of tank 20 and through fluid motor.38 via check valve 36. At the same time, exhaust valve 40 is closed and valve 42 opened by apparatus 30 so that the-fluid now flowing through motor 38 via check valve 36 returns to tank 32 via check valve 39. Open valve 42 permits the vapor pressure in chamber 22 to escape to the atmosphere so that tank 22 can refill.

A portion of the fluid flowing out of one or the other of the tanks 20 or 22 also returns to reservoir 24 via valve 46 which may be controlled by apparatus 30 or may be manually or otherwise adjusted to provide a suitable flow of liquid into reservoir 24 for vaporization within boiler 26. As mentioned above, while water is one suitable material which exists in the vapor and gaseous phase and can be suitably used in this arrangement, any other suitable fluid which can be satisfactorily converted from its liquid to its vapor phase can be employed.

Reference is now made to FIG. 2 which shows another embodiment of the invention of this application. In this arrangement, the fluid motor 50 is an AC. hydrostatic motor which is capable of converting reciproeating motion into continuous shaft rotation, e.g., by means of a reciprocating or swash plate motor. Such AC. motors are well known in the art, and not further discussion of them isnecessary. This embodiment of the invention operates in the same fashion as the embodiment illustrated in FIG. 1 as discussed above with two tanks 52 and 54 alternately filled and emptied of the working fluid by means of vapor generated within boiler 54 and alternately directed to tanks 52 and 54 by master valve 56 which is under the control of a suitable control mechanism 58. A reservoir 60 is provided in the system and a valve 62 connects reservoir 60 to the fluid in the two tanks for providing additional fluid for vaporization in boiler 54. Boiler or vapor generator 54 produces cyclic pressure at N times the hydraulic motor 50 shaft rotation frequency, N being any suitable integer.

Reference is now made to FIG. 3 which depicts one suitable arrangement for injecting fluid into a boiler or simlar device, such as boiler 26 depicted in FIG. 1, for conversion into a vapor phase such as steam. The fluid thus injected is preferably divided into droplets which are as small as possible to minimize the time required for vaporization. In the embodiment of FIG. 3, fluid enters vessel through a conventional inlet valve 72. Vessel 70 is constructed or associated with piezo electric, magnetic restrictive, or solenoid driven material or structure so that the volume of vessel 70 is cyclically changed due to the harmonic residence of its elastic walls. Thus, the fluid which enters vessel 70 through inlet check valve 72 is cyclically injected into boiler 74 for conversion from a liquid to gaseous phase. This injection technique also finely divides the injected droplets. In fact, inlet valve 72 may not be required in operation becasue water is injected into the boiler steam generator 74 at such high rate to make back flow through the normally small orifices which will preferably be employed a negligible problem.

FIG. 4 illustrates another arrangement similar to that of FIG. 1 whereby the fluid which is converted into vapor is derived directly from the vessels themselves. In this arrangement, fluid lines 76 and 78 are connected to vessels 80 and 82 as shown. Valves 86 and 88 connect lines 76 and 78, respectively, to a conventional boiler or other steam generator 90 which converts the received fluid from its liquid to its gasous phase. Master valve 92 directs the fluid to tanks 80 and 82 alternately as in the embodiment of FIG. 1, and the fluid forced from one tank by vapor pressure flows through actuator or fluid motor 94 and refills the other tank in the same manner as in FIG. 1. Valves 86 and 88 are operated by control mechanism which also controls master valve 92 so that fluid is drawn from the tank which is refilling to provide fluid to be vaporized to provide the pressure which imparts motion to the working fluid. As in the other embodiments, vapor pressure in the tank being refilled is vented to the atmosphere through valves 102 and 104. Valves 86 and 88 are cyclically opened to cause flow into boiler 90. The heat available from the walls of boiler 90 preferably converts the liquid to vapor. Preferably the period during which water flows into boiler is related to the speed of sound in the vapor compared to its speed in the liquid and upon the geometrical proximities of valves and reservoirs.

FIG. 5 illustrates another embodiment of the invention similar to that of FIG. 1 in which a hydrostatic resonant coupled acoustic pump is employed to draw liquid from the drive system to be converted into vapor within boiler 110. As in the arrangement of FIG. 1, tanks 11 2 and 114 are alternately emptied and refilled with the working fluid by means of vapor pressure which is generated in boiler and alternately directed into the respective tanks by master valve 116 which is controlled by a suitable control 120.

Whenever additional working fluid, e.g. water, is required for boiler 110, tuning fork 120 is set in motion by any suitable mechanism. For example, in this embodiment tuning fork 120 is shown connected to the hydrostatic motor 124 by some suitable linkage mechanism. The horn may also be driven by cams or strikers from the motor 124. Horn 122 magnifies the acoustic excursion generated by fork 120 by the inverse ratio of the steam chamber inlet area to the base area so that water is pushed from the region of tuning fork 120 through horn 122 and injected into boiler 11! as fine droplets.

FIG. 6 illustrates one particular reservoir which is believed to be of particular use in conjunction with a system such as depicted in FIGS. 15 and in the other Figures discussed below. In this arrangement, the returning hot water enters tank 126 and is kept from the walls thereof by a thin-walled steam quench 128 which is provided with a number of holes which permit the returning hot water to exit therefrom. Quench 128 thus prevents the return water from thermally shocking the reservoir tank walls and also allows the heat stored in that wall to generate steam within the reservoir tank itself.

FIG. 7 illustrates yet another embodiment of the invention similarly to the basic D.C. hydrostatic drive system shown in FIG. 1. In this arrangement, as in the others, fluid from two vessels 130 and 132 is alternately forced through a fluidic motor 134 via-suitable check valves. However, this particular arrangement differs from those illustrated above in that the fuel which is burned to generate the heat which is converted to mechanical energy is also employed as the working fluid. The fuel, e.g. methane, is stored in a suitable reservoir 136 and added to the system at point 138 where the working fluid exists from fluidic motor 134. The working fluid which is also the fuel then returns to the tank 130 or 132 which is being refilled through the associated check valve.

Part of the liquid which flows out of the tank 130 or 132 which is being depleted is also diverted through either valve 140 or 142, which are both controlled by the control mechanism 134, into either boiler or 152, respectively, where heat is added to cause the fuel to change from a liquid to a gaseous state and expand into the associated tank so as to force the working fluid therein out its exit to drive fluid motor 138 and refill the other tank. The gas in the tank which is being refilled, for example, tank 130, is also exhausted to a burner via either valve 164 or 166. An oxidant from a suitable reservoir 168 is also supplied to burner 160 for combusting the gaseous fuel. Thus the liquid fuel serves as the working fluid and the vapor which must be exhausted from the tank being refilled then combusted to provide a compact heat source. Floating head barriers may be disposed in each of the vessels 130 and 132 to increase heat transfer between the gas and fluid stages.

FIG. 8 illustrates yet another modification of the basic hydrostatic drive system set forth in FIG. 1. In this arrangement, heat exchange from the vapor expanding within the reservoir tank to feed water on its way to the boiler or vapor generators provides a simple regenerative system. Tanks 170 and 172 are filled with a suitable working fluid as in the other embodiment, and this working fluid is alternately forced out of one of the tanks 170 and 172 through fluidic 'rnotor 174 to refill the other tank. Further, some of the fluid forced from tank 172 or 174 is diverted into line 176, and from line 176, the working fluid thus diverted flows through either coil 178 or 180 depending on which of the check valves 184 and 186 is open. Valves 184 and 186 are under the control of a suitable control apparatus 190 as shown so that the fluid is normally permitted to flow only through the coil 178 or 180 which is in the tank being refilled. The fluid passing through coil 178 or 180 absorbs heat from the working fluid in the surrounding tank and from the hot vapor in that tank as it is exhausted. Thus, the feed fluid enters either boiler 200 or 202 at an elevated temprature, which reduces the quantity of heat necessary to convert the fluid from a liquid to a vapor phase before injection into tank 170 FIG. 9 illustrates another embodiment of the invention which is regenerative in the sense that heat in the working fluid is employed, at least in part, to generate the vapor pressure which forces that fluid for one tank through the motor to refill the other tank. In the embodiment, two tanks 210 and 212 are designed to be filled to a maximum level which is just below the porous heat storage bed 214 with a fluid which will change from liquid to vapor phase at a suitable temperature. When heat is added to one side of storage bed 214, for example, the side associated with tank 210, the added heat causes a conversion of some of the fluid in vessel 210 from its liquid to its vapor phase resulting in a volume expansion which force part of the remaining fluid out the exit of vessel 210 and through a fluidic motor 220 to refill tank 210. When tank 210 has been emptied to a desired level, the procedure is reversed and heat is added to the portion of the porous heat storage bed 214 associated with tank 212. Next the working fluid in tank 212 is partially vaporized so that part of the remaining fluid is out the exit of tank 212 and through fluidic motor 220 into vessel 210.

Meanwhile in the tank that is being refilled with working fluid, bed 214 is absorbing heat from the fluid entering that tank. This heat is retained in bed 214 until that tank has been refilled and additional heat can thereafter be added to cause partial vaporization of the fluid in that tank. Thus, the system is regenerative in the sense that a portion of the heat which is imparted to the working fluid and not initially used to generate mechanical output is thereafter removed from the fluid and reused to generate mechanical output.

FIG. 10 shows yet another embodiment of the inven tion in which heat is exchanged in the system in a manner similar to an Ericson cycle. In this arrangement, heat is generated, for example, by burning methane or some other suitable fuel in burner 218, and then conducted into the vessel through coils 220 and 222. Suitable valves may be provided for switching the flow of the exhaust gases and the heat to the respective tanks for cyclically empying and refilling tanks 224 and 226. The fluid re-enterting either of the tanks also passes through a coil 228-or 230 before being emptied into vessel 226 or 224, respectively, so that the heat which exists in the fluid which is leaving the tank on its way through motor 232 is in part given back to the water which is returning to the vessel Similarly, coils 242 and 244 are provided to at least partially cool the fluid exiting from motor 232.

FIG. 11 shows yet another embodiment of the invention whereby the heat imparted to the working fluid which would be otherwise lost is in part saved and used to generate a mechanical output. In this embodiment, two tanks 240 242 are alternately filled and emptied with working fluid which passes through conventional fluid motor 244. Fuel such as kerosene, natural gas, powdered coal or LP gasform a suitable source 246 is combined with a suitable oxidant and combusted in a suitable burner 248 after passage through a valve 250 which may be manually or automatically adjusted to permit flow of a desired amount of fuel. Heat from the burner 248 is employed to convert the working fluid injected into boilers 252 and 254 into vapor, in which state it is directed into tanks 240 and 242, respectively. Suitable valve means may be provided in boilers 252 and 254' if necessary or desirable.

A portion of the fluid exiting from the tank 240 and 242 being emptied is drawn through either coil 260 or 262 into boiler 252 or 254, respectively. Valves 266 and 268 control the flow of fluid into coils 260 and 262 and these valves are controlledin turn by a suitable control apparatus 270 which insures that fluid will enter only that boiler which is supplying vapor to the tank which is being emptied. Thus, if fluid is to be forced out of tank 240 by the addition of vapor to the top thereof, then valve 268 will be open and valve 266 closed so that the fluid which passes valve 268 will pass through coil 262 and be injected by a suitable injector into boiler 254. As the working fluid passes through coil 262, heat is imparted to it by the burner 248 to preheat the fluid so that it arrives at the boiler at an elevated temperature, thus considerably increasing the amount of vapor that can be injected into the tanks 240 and 242 within any given period of time.

. Further, water or other fluid existing from the tank being emptied passes through heat exchanger 270 or 272 before passage through fluid motor 244. These heat exchangers reduce the temperature of the working fluid on its way to motor 244 and thereby decreases the possibility of damage to the fluid motor because of exposure to overheated fluid. The heat in the fluid which enters heat exchanger 272 from the tank 240 or 242 being emptied is in part transferred to the fluid which is leaving motor 244 and is being returned to the tank 240 or 242 which is being refilled so that this heat raises the temperature of the fluid in the tank being refilled. I

Reference is now made to FIG. 12 which shows another embodiment of the engine whereby water derived as a by-product of hydrocarbon or other fuel combustion is employed as a make-up supply for the working fluid of the system and further as means of rejecting into the atmosphere heat which is not converted into useful mechanical output. This heat transfer management technique significantly simplifies the apparatus required for converting chemical potential energy into shaft work and increases the efficiency compared to Otto or Diesel cycle processes.

Hydrocarbon fuels yield carbon monoxide and water when burned to completion in oxygen or oxygenbearing stmospheres. The amount of water produced compared to the amount of carbon monoxide produced depends upon the hydrogen to carbon ratio of the fuel being burned. In common liquid petroleum fuels, the amount of water produced is approximately equal to the amount of fuel burned. In liquefied petroleum gas fuels (butane, propane, methane, etc.) combustion products tend to an even greater extent to be water. vaporization of water at a fixed pressure fixes the boil off temperature. At sea level the temperature for boil off is about 212F. and, at lower atmospheric pressure, the boil off temperature is correspondingly lower. The

embodiment of the invention as illustrated in FIG. 12

uses this by-product of hydrogenous fuel combustion as a make-up working fluid supply.

In this embodiment, as in the other embodiments, two reservoir tanks 276 and 278 are alternately discharged and refilled with working fluid which flows from one tank to the other through fluid motor 280,

' thus, converting the pressure of the working fluid and the kinetic energy embodied in the flow of that fluid into useful output shaft power. The flow of the working fluid is also cyclically directed via valves 282 and 284 into the boilers 286 and 288 which provide the vapor pressure for forcing the working fluid cyclially from tanks 278 and 280. Fuel from a suitable source 300 is directed via valve 302 into boilers 286 and 288, respectively. Valve 302 may be under the control of a suitable mechanism such as control apparatus 304 which con trols valves 282 and 284 as well as valves 306 and 208 j in the same fashion as discussed above.

In contrast to the embodiment illustrated in FIG. 11, the fuel derived from source 300 is combusted within boilers 286 or 288 which alternately may be any other type of combustion device suitable for combusting the fuel and directing the combined vapor and exhaust gases therefrom. The exhaust gases of combustion together with the water or other vapor produced from the working fluid are alternately passed into tanks 276 and 278 to force the fluid therein to flow out the exit and pass through the fluid motor 280. In this fashion, the water vapor which is derived from the burning of the hydrocarbon fuel and thus added to the system at least in part replaces the vapor which is exhausted to the atmosphere by the alternate opening of valves 310 and 312 during alternate refilling of tanks 276 and 278.

A portion of the fluid existing from motor 280 also passes through valves 306 and 308 which are under control of apparatus 304 and enter the evaporator radiator devices 320 and 322. These devices are preferably provided with an open top or are'otherwise accessible to the atmosphere so that the fluid-that enters these devices evaporates to the atmosphere taking with it heat imparted to the evaporating fluid by the working fluid which passes through coils 324 and 326 on its way to fluid motor 280. Part of the heat imparted to the fluid in evaporators 320 and 322 is also transmitted to the fluid returning to tanks 276 and 278 via coils 330 and 332. Thus, part of the heat of the working fluid in tanks 276 and 278 is employed to pre-heat the fluid returning 9 to the tanks after passing through motor 280 and part is vented to the atmosphere so that the fluid which is passed through motor 280 is at a temperature which will not damage the motor.

As in the other embodiments, the working fluid in this embodiment may be water or may be more sophisticated solutions, e.g., mixtures of water and other compounds which might, for example, prevent freezing, increase lubricity, increase or decrease heat transfer, or aid or retard absorption and retention of combustion gases. Conversely, the working fluid may contain a less dense compound or particle which floats upon its surface, thus providing insulation between the combustion gases and working fluid during the period that the pressure is being transmitted in from the hot gases to the working fluid in the reservoir. Compounds added to the working fluid may be separated from vaporizable or combustible portions of the working fluid prior to admission to the generator-combustor sections such as boilers 286 and 288.

By utilization of common and inexpensive steels, ceramics, bearings, valves and other hardware, the embodiment of the invention illustrated in FIG. 12, as well as the embodiments of the other figures, may be designed to operate at temperatures of, for example, 2,000F. and 6,000 lbs. per square inch at the inlet of the tank receiving the vapor through 160F. or lower by use of heat-dams, insulation, and other arrangements such as flow deflectors and surface coatings. Conversely, the upper portion of the reservoir walls may be maintained at temperatures exceeding 1,200F. if desired, thus allowing heat input and storage previous to steam generation by conduction of heat into the fluid at the time during the filling of the reservoir tank that the fluid level reaches the high wall temperature level.

The basic versatility of the embodiment'of FIG. 12 is further illustrated by the potential of using more than, two fluid reservoirs. Manufacture of 100 horsepower modules consisting of two reservoirs and one motor actuator allows engine units of 200 HP, 400 HP, 600 HP, and 1,000 HP, or more, to be assembled simply by joining the output shafts of each motor to a common output shaft. Such an output shaft would only have the minimum fabrication requirement of being attachable per the application function and would not involve the various sophistications characteristic of internal combustion engine crankshafts. Similarly multiple reservoir modules mayby hydraulically connected to a single motor.

The vast variety of hydrostatic, hydraulic, and hydrodynamic actuators further exemplifies particuarly the versatility of the embodiment of FIG. 12 in various applications only being served today by complex mechanisms involving clutches, transmissions, angle drives, universal joints, and differentials. The probability of costly failure is inherently reduced in the embodiment. FIG. 12, as well as the other embodiments, compares favorably to conventional internal combustion reciprocating engines by the reduced number of working parts, the reduced metal to metal relative motion, and the reduced gyratory forces involved. The ability to achieve high horsepower to weight ratios at high efficiencies, particularly when materials selections typical to aircraft turbines are made, makes the engine shown in FIG. 12 preferable to turbines for propeller driven aircraft.

Reference is now made to FIG. 13 which shows an other embodiment of the invention which is somewhat similar to the conventional Stirling cycle engine. The

Stirling cycle distinguishes itself primarily as one employing regeneration techniques in which heat is transferred from the working fluid into a thermal reservoir as a working fluid begins its expansion. After mechanical output has been generated, the stored heat is readded to the cooled working fluid as it is being reheated to the maximum temperature of the cycle.

The embodiment of the invention illustrated in FIG. 13 is similar in that it is regenerative, but this embodiment also employs advantageous aspects of both the liquid and gas phases in the process of converting heat into mechanical work. In the embodiment illustrated in FIG. 13, heat, for example, produced by combustion of hydrocarbon or other fuels, nuclear fission, or fusion is transferred into vapor phases of the working fluid at heat source 350 which may be, for example, a boiler such as in the other embodiments.

As in the other embodiments, heat from source 350 is employed to convert working fluid from a liquid to a gaseous phase and to direct the vapor pressure thus generated alternately into tanks 352 and 354 so that working fluid is forced out of one of the tanks and through fluidic motor 356 to refill the other tank. A portion of the working fluid which is forced out of each of the tanks is also employed to provide liquid for conversion to a gaseous phase. However, in this embodiment, fluid on its way to a vapor generator such as a boiler passes through a heating coil in the tank being refilled so as to absorb as much of the heat as possible from the fluid entering that tank and also to absorb as much heat as possible from an extended heat transfer surface which is mounted adjacent to the coil through which the fluid passes. For example, a portion of the fluid exiting from tank 352 passes through valve 360 and coil 362 which is mounted in tank 354 as shown. During the time that tank 354 refilling, working fluid on its way to boiler 366 passes through tank 354 via coil 362. The fluid returning to tank 354 from motor 356 passes through negative heat rejection coil 364 and the fluid returning to tank 352 through negative heat rejection coil 365.

Further, an extended heat transfer surface comprising coil 367 within tank 354 is mounted adjacent coil 362. Coil 367 absorbs heat from the working fluid reentering tank 354 and also absorbs heat from the exhaust gases generated by source 350 which are exhausted to the atmosphere via coil 367 as well as coil 370. The heated fluid existing from coil 362 is injected into boiler 366 where it is converted into its vapor phase and that vapor then transmitted to tank 352 to force the working fluid therein out its exit and through motor 356. Coils 368 and 370 within tank 352 operate similarly when that tank is being refilled, and tank 354 is being emptied. As shown, coils 362 and 368, which each preferably comprise a hollow coil, are connected to an exhaust 372 so that, for example, the hot combus-.

tion gases are transmitted through coils 366 and 368 so that the heat of the combustion gases can, at least in part, be imparted to the working fluid which is to be vaporized and eventually employed to generate a mechanical output. Nuclear loop transfers, of course, would not need an exhaust but preferably employ a similar circuit to optimize the efficiency of energy conversion.

Reference is now made to FIG. 14 which shows yet another embodiment of the invention. In this arrangement, two or more working fluids are employed to permit extension of the thermal gradiant to higher and lower temperatures than allowed by a single working fluid. This arrangement offers considerable advantages from the standpoint of thermodynamics. In this embodiment, as in the embodiment of FIG. 11,-fuel from a suitable source 400 is burned by a suitable burner 402 adjacent conventional boilsers 406 and 408. Vapor thus generated is alternately directed into reservoir tanks 410 and 412, one of which is continually emptying and refilling the other through fluidic motor 414 and thus generating a continuous and useful mechanical shaft output.

However, fluid issuing from either of the tanks 410 or 412 passes through a heat exchanging coil 414 or 416 on its path through motor 141, thus imparting heat to the fluid in lines 420 and 422 respectively which will normally contain working fluid having a different critical point than the working fluid in tanks 410 and 412. The heat thus imparted causes the fluid in lines 420 and 422 to change from its liquid to its vapor phase and the resulting expansion of the working fluid causes the fluid in tanks 424 and 426 alternately to be forced through a second fluid motor 426 which may be in parallel with the first motor for combining the mechanical shaft output.

A number of combinations of working fluids can be employed in this arrangement. A few examples are mercury and water, mercury and potassium-sodium eutectic, water and freon, water and silicone fluids, freon and liquified gases and many others. A simple extension of the illustrated system permits the development of engines which use three or four or more working fluids.

Reference is now made to FIG. 15 which shows yet another embodiment of the invention in which two hydrostatic systems, each having two tanks are employed to operate a single shaft with two motors 402 and 404 connected in parallel. It should be apparent that any number of systems such as illustrated above can connected together to generate any desired power output.

FIG. 16 shows yet another embodiment of the invention wherein elastic diaphragms 410 and .412 are connected between two working fluids. The diaphragms separate each of the two tanks 416 and 418 into an upper and lower compartment. The fluid in the upper compartment, for example, the fluid in the upper part of tank 418 can be expanded for any suitable means, for example, by heating in boiler 420 with the result that the downward pressure exerted by elastic diaphragm 412 forces the fluid in the lower portion of tank 418 out of its exit and through hydrostatic motor 420 thus deriving a mechanical output. The fluid thus forced from tank 412 then refills the bottom portion of tank 410 which then forces the fluid out of the upper portion and thereof and into the upper portion of tank 418 via valve 422. The process is then reversed with the fluid in the lower portion of tank 410 being forced out by the fluid expanded by boiler 426 and directed into the upper portion of tank Similarly pistons bellows, and floating particles may be used to separate the fluids.

Reference is now made to FIG. 17 which shows a hydrostatic drive system employing only a single reservoir tank 424. This embodiment which could be used, for

example, in a rocket system for travel in outer space employs the heat generated by the fuel which is combusted to supply the rocket thrust to impart motion to the fuel whichthen serves as the working fluid for conventional hydrostatic or other similar motor 426. The heat generated in combustion chamber 428 which is normally wasted is employed-to convert the fuel fluid from a liquid to a gaseous state in pressure source 430 so that the pressure thus generated forces the fuel fluid in tank 424 out its exit and through motor 426 to be burned in combustion chamber 428. A cooling arrangement 432 can be disposed adjacent the tank 424 for condensing some of the vapor added to tank 424 into a liquid which can then be used as the working fluid and combusted after passage through motor 426.

FIG. 18 shows a modification of the embodiment of FIG. 7 whereby the heat generated by combusting the working fluid in a combustion chamber 440, for example, to generate thurst to propel a rocket or other vehicle is employed by a heater 442 which has coils disposed about reservoir tank 444 which .is filled with a suitable fuel fluid. The heat added to the fluid in tank 444 by heater 442 causes a portion of it to be converted into a vapor stateand expand, thus forcing part of the working fluid in chamber 444 out past valve 446 and through fluid motor 448 to combustion chamber 440 where it is burned. Thus, the waste heat from the combustion is employed to generate the mechanical output which can be employed in the device for any purpose desired.

The above discussed embodiments of the invention can of course be satisfactorily employed in a number of applications. These include, but are not limited to:

a. Air heating and cooling,

b. Lawn mowers,

0. Motor generator units,

(1. Garden Tractors,

e. Sump pumps,

f. Garbage Disposal and Compaction,

g. Irrigation pumps,

h. I Electrical Power Generation i. Compressor Stations j. Oil and Gas Drill Drilling and Pumping k. Elevators and Lifts 1. Conveyors m. Ore Crushers and Pulverizers n. Grain Mills 0. Scrap Shredders and Compactors Automobile Rail Cars Bus and Train Truck and Tractors Other Farm Equipment Highway construction equipment v. Pleasure and Commercial Boats w. Aircraft The following Table represents a few resultant engine horsepowers and weights based upon the use of fired boiler rated steels and conventional hydrostatic motors as derived. from computer modeling studies.

TABLE Maximum Total Engine Continuous No. of Full Torque Engine Shown in HP Reservoirs RPM Range Dry Weight (pounds) FIG. 12 5 2 l2000 30 or NCO-20,000 FIGv l2 l 4 IOU-2,000 72 or LOGO-20,000 FIG. I3 50 4 lOO2,000 128 FIG. 13 100 4 IOU-2,000 l82 FIG. 11 300 Z lOO2,000 287 FIG. ll 600 4 100-2,000 665 t The use of titanium alloys, composites, and coatings will permit considerable improvement in the weight to power ratios of the Table. However, for most applications the Table ratios will be sufficient.

Many changes and modifications in the above discussed embodiments of the invention can of course be made without departing from the scope of the invention. Accordingly, that scope is intended to be limited only by the scope of the appended claims.

What is claimed is:

l. A process for converting heat into work by repetitious cycles, each cycle of which comprises the steps of:

l. utilizing a high energy gaseous vapor within a first energy input zone containing a portion of fluid medium at a low energy level to thereby increase the energy level of the fluid medium in said first energy input zone,

2. communicating the increased energy level medium within said first energy input zone in a first fluid energy transmitting relationship with an energy conversion zone and causing flow of increased energy level medium out of said first energy input zone and flow of increased energy level medium into said energy conversion zone,

3. converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said first fluid energy transmitting relationship,

4. communicating reduced energy level medium within said energy conversion zone with a second en-' ergy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said second energy input zone,

5. utilizing a high energy gaseous vapor within said second energy input zone to thereby increase the energy level of the fluid medium in said second energy input zone,

6. communicating the increased energy level medium within said second energy input zone in a second fluid energy transmitting relationship with said energy conversion zone and causing flow of increased energy level medium out of said second energy input zone and flow of increased energy level medium into said energy conversion zone,

7. converting within said energy conversion zone a portion of the energy of said increased energy level medium in said second fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said second fluid energy transmitting relationship,

8. communicating reduced energy level medium within said energy conversion zone with said first energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said first energy input zone, and

9. obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to fluid medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relation ships.

2. A process as defined in claim 1 wherein said high energy gaseous vapor is obtained by alternately com municating the increased energy level medium in said first and'second fluid energy transmitting relationships with a high energy medium storage zone to cause flow therein alternately communicating the high energy medium in said storage zone with said first and second energy input zones and adding heat to the high energy medium communicating between said storage zone and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

3. A process as defined in claim 1 wherein, during the flow of fluid medium into said second energy input zone as aforesaid in step (4), said second energy input zone is communicated with the atmosphere and, during the flow of fluid medium into said first energy input zone as aforesaid in step (8), said first energy input zone is communicated with the atmosphere.

4. A process as defined in claim 3 wherein said medium is a combustible material in the presence of an oxidant and wherein the fluid medium communicated withthe atmosphere is mixed with an oxidant and combusted to provide the source of added heat.

5. A process as defined in claim 1 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with first and second heat exchange zones disposed in heat exchange relation with said first and second energy input. zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

6. A process as defined in claim 1 wherein said high energy vapor is obtained by providing a first porous heat storage bed within said first energy input zone which absorbs heat during the flow of medium into said first energy input zoneas aforesaid in step (8) and to which heat is thereafter added to generate said high en ergy vapor within said first energy input zone which is utilized as aforesaid in step (I) and providing a second porous heat storage bed within said second energy input zone which absorbs heat during the flow of medium into said second energy input zone as aforesaid in step (4) and to which heat is thereafter added to generate said high energy vapor within said second energy input zone which is utilized as aforesaid in step (5).

7. A process as defined in claim lwherein the heat added in obtaining said high energy vapor is created by continuously combusting fuel in the presence of an oxidant and confining the flow of the products of combustion along flow paths which include first and second heat exchange zones disposed in heat exchange relation with the fluid medium within said first and second energy input zones respectively.

8. A process as defined in claim 7 wherein said high energy vapor is obtained by communicating a third heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone as aforesaid in step (4) so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said third heat exchange zone and by communicating a fourth heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone as aforesaid in step (8) so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said fourth heat exchange zone.

' 9. A process as defined in claim 8 wherein the fluid medium flowing between said energy conversion zone and said third and fourth heat exchange zones is cooled.

10. A process as defined in claim 7 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

11. A process as defined in claim 1 wherein said high energy vapor is obtained by communicating a first heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone as aforesaid in step (4) so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said first heat exchange zone and by communicating a second heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone as aforesaid in step (8) so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said second heat exchange zone.

12. A process as defined in claim 1 wherein the fluid medium flowing out of said energy conversion zone and into said first and second energy input zones as aforesaid in steps (4) and (8) flows in heat exchange relation with the fluid medium in'said first and second fluid energy transmitting relationships so that the fluid medium flowing into said energy input zones has an increased temperature energy level with respect to the associated fluid medium flowing out of said energy conversion zone.

13. A process as defined in claim 12 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.

14. A process as defined in claim 12 wherein said fluid medium is H 0 and wherein the heat added in obtaining said high energy vapor is generated by combusting a hydrocarbon fuel with an oxidant, and wherein said high energy vapor is obtained by alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and then alternately communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones so as to enter therein as said high energy vapor.

15. A process as defined in claim 1 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths, combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.

16. A process as defined in claim 1 wherein said fluid medium is H 0 and wherein the heat added in obtaining said high energy vapor is generated by combusting a hydrocarbon fuel with an oxidant, and wherein said high energy vapor is obtained by alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and then alternately communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones so as to enter therein as said high energy vapor.

17. In a process for converting heat into work by repetitious cycles, each cycle of which includes the steps of utilizing a high energy gaseous vapor within a first energy input zone containing a'portion of fluid medium at a low energy level to thereby increase the energy level of the fluid medium in said first energy input zone, communicating the increased energy level medium within said first energy input zone in a first fluid energy transmitting relationship with an energy conversion zone and causing flow of increased energy level medium out of said first energy input zone and flow of increased energy level medium into said energy conversion zone, converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said first fluid energy transmitting relationship, communicating reduced energy level medium within said energy conversion zone with a second energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said second energy input zone, utilizing a high energy gaseous vapor within said second energy input zone to thereby increase the energy level of the fluid medium in said second energy input zone, communicating the increased energy level medium within said second energy input zone in a second fluid energy transmitting relationship with said energy conversion zone and causing flow of increased energy level medium out of said second energy input zone and flow of increased energy level medium into said energy conversion zone, converting within said energy conversion zone a portion of the energy of said increased energy level medium in said second fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said second fluid energy transmitting relationship, and communicating reduced energy level medium within said energy conversion zone with said first energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said first energy input zone, the improvement in combination therewith which comprises the step of obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to fluid medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships.

18. Apparatus for converting heat into work by repetitious cycles which comprises 1. means defining a first energy input zone within which a high energy gaseous vapor is utilized to increase the energy level of fluid medium at a low energy level therein,

2. means defining a second energy input zone within which a high energy gaseous vapor is utilized to increase the energy level of the fluid medium at a low energy level therein,

3. means defining an energy conversion zone,

4. means for alternately communicating the increased energy level medium within said first and second energy input zones in first and second fluid energy transmitting relationships with said energy conversion zone and for causing flow of increased energy level medium out of said first and second energy input zones and flow of increased energy level medium in a liquid phase into said energy conversion zone,

5. means for converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first and second fluid energy transmitting relationships into work thereby reducing the energy level of said medium in said first and second energy transmitting relationships,

6. means for alternately communicating reduced energy level medium in a liquid phase within said energy conversion zone with said first and second energy input zones and for causing reduced energy level medium in a liquid phase to flow out of said energy conversion zone and reduced energy level medium to flow alternately into said first and second energy input zones, and

7. means for obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to medium which has been energized by energy transfer with fluid medium in. said first and second fluid energy transmitting relationships.

19. Apparatus as defined in claim l8 wherein said high energy'gaseous vapor obtaining means includes means defining a high energy medium storage zone, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with high energy medium in said storage zone to cause flow therein, means for alternately communicating the high energy medium in said storage zone with said first and second energy input zones, and means for adding heat to the high energy medium communicating between said storage zone and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

20. Apparatus as defined in claim 18 including means for communicating said second energy input zone with the atmosphere during the flow of fluid medium into said second energy input zone, and means for communicating said first energy input zone with the atmosphere during the flow of fluid medium into said first energy input zone.

21. Apparatus as defined in claim 20 wherein said medium is a combustible material in the presence of an oxidant and means for combusting the fluid medium communicated with the atmosphere with an oxidant to provide the source of added heat.

22. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second heat exchange zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, means for alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and means for adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

23. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining a first porous heat storage bed within said first energy input zone for which absorbing heat during the flow of medium into said first energy input zone, means for thereafter adding heat to said first porous heat storage bed to generate said high energy vapor within said first energy input zone, means defining a second porous heat storage bed within said second energy input zone for absorbing heat during the flow of medium into said second energy input zone, and means for thereafter adding heat to said second porous heat storage bed to generate said high energy vapor within said second energy input zone.

24. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means for continuously combusting fuel in the presence of an oxidant and means for confining the flow of the products of combustion along flow paths which include first and second heat exchange zones disposed in heat exchange relation with the fluid medium within said first and second energy input zones respectively.

25. Apparatus as defined in claim 24 wherein said high energy vapor obtaining means comprises means defining a third heat exchange zone disposed in heat exchange relation with a fluid medium in said second energy input zone means for communicating said third heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said third heat exchange zone, means defining a fourth heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone means for communicating said fourth heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said fourth heat exchange zone.

26. Apparatus as defined in claim 25 including means for cooling the fluid medium flowing between said energy conversion zone and said third and fourth heat exchange zones.

27. Apparatus as defined in claim 24 wherein said high energy vapor obtaining means includes means defining first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second heat exchange zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, means for alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and means for adding heat to the increased temperature energy level medium communicating be- .tween said first andsecond heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.

28. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining a first heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone means for communicating said first heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said first heat exchange zone, means defining a second heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy'input zone and meansfor communicating said second heat exchange zone in s'eriesbetween the fluid medium flowing out of said energy conversion zone and into said first energy input zone so that the fluid medium'flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said second heat exchange zone.

29. Apparatus as defined in claim 18 including means for confining the flow of the fluid medium out of said energy conversion zone and'into said first and second energy input zones in heat exchange relation with the fluid medium in said first and second fluid energy transmitting relationships so that the fluid medium flowing into said energy input zones has an increased temperature energy level with respect to the associated fluid medium flowing out of said energy conversion zone.

30. Apparatus as defined in claim 29 wherein said high energy vapor obtaining means includes means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths, means for combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and means for directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.

31. Apparatus as defined in claim 29 wherein said fluid medium is H 0 and wherein said high energy vapor obtaining means includes means for combusting a hydrocarbon fuel with an oxidant, and means for al- 

1. A process for converting heat into work by repetitious cycles, each cycle of which comprises the steps of:
 1. utilizing a high energy gaseous vapor within a first energy input zone containing a portion of fluid medium at a low energy level to thereby increase the energy level of the fluid medium in said first energy input zone,
 2. communicating the increased energy level medium within said first energy input zone in a first fluid energy transmitting relationship with an energy conversion zone and causing flow of increased energy level medium out of said first energy input zone and flow of increased energy level medium into said energy conversion zone,
 3. converting within said energy conversion zone a portion of the energy of said increased Energy level medium in said first fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said first fluid energy transmitting relationship,
 4. communicating reduced energy level medium within said energy conversion zone with a second energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said second energy input zone,
 5. utilizing a high energy gaseous vapor within said second energy input zone to thereby increase the energy level of the fluid medium in said second energy input zone,
 6. communicating the increased energy level medium within said second energy input zone in a second fluid energy transmitting relationship with said energy conversion zone and causing flow of increased energy level medium out of said second energy input zone and flow of increased energy level medium into said energy conversion zone,
 7. converting within said energy conversion zone a portion of the energy of said increased energy level medium in said second fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said second fluid energy transmitting relationship,
 8. communicating reduced energy level medium within said energy conversion zone with said first energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said first energy input zone, and
 9. obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to fluid medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships.
 2. means defining a second energy input zone within which a high energy gaseous vapor is utilized to increase the energy level of the fluid medium at a low energy level therein,
 2. A process as defined in claim 1 wherein said high energy gaseous vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with a high energy medium storage zone to cause flow therein alternately communicating the high energy medium in said storage zone with said first and second energy input zones and adding heat to the high energy medium communicating between said storage zone and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.
 2. communicating the increased energy level medium within said first energy input zone in a first fluid energy transmitting relationship with an energy conversion zone and causing flow of increased energy level medium out of said first energy input zone and flow of increased energy level medium into said energy conversion zone,
 3. converting within said energy conversion zone a portion of the energy of said increased Energy level medium in said first fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said first fluid energy transmitting relationship,
 3. A process as defined in claim 1 wherein, during the flow of fluid medium into said second energy input zone as aforesaid in step (4), said second energy input zone is communicated with the atmosphere and, during the flow of fluid medium into said first energy input zone as aforesaid in step (8), said first energy input zone is communicated with the atmosphere.
 3. means defining an energy conversion zone,
 4. means for alternately communicating the increased energy level medium within said first and second energy input zones in first and second fluid energy transmitting relationships with said energy conversion zone and for causing flow of increased energy level medium out of said first and second energy input zones and flow of increased energy level medium in a liquid phase into said energy conversion zone,
 4. A process as defined in claim 3 wherein said medium is a combustible material in the presence of an oxidant and wherein the fluid medium communicated with the atmosphere is mixed with an oxidant and combusted to provide the source of added heat.
 4. communicating reduced energy level medium within said energy conversion zone with a second energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said second energy input zone,
 5. utilizing a high energy gaseous vapor within said second energy input zone to thereby increase the energy level of the fluid medium in said second energy input zone,
 5. A process as defined in claim 1 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones aS said high energy vapor.
 5. means for converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first and second fluid energy transmitting relationships into work thereby reducing the energy level of said medium in said first and second energy transmitting relationships,
 6. means for alternately communicating reduced energy level medium in a liquid phase within said energy conversion zone with said first and second energy input zones and for causing reduced energy level medium in a liquid phase to flow out of said energy conversion zone and reduced energy level medium to flow alternately into said first and second energy input zoneS, and
 6. A process as defined in claim 1 wherein said high energy vapor is obtained by providing a first porous heat storage bed within said first energy input zone which absorbs heat during the flow of medium into said first energy input zone as aforesaid in step (8) and to which heat is thereafter added to generate said high energy vapor within said first energy input zone which is utilized as aforesaid in step (1) and providing a second porous heat storage bed within said second energy input zone which absorbs heat during the flow of medium into said second energy input zone as aforesaid in step (4) and to which heat is thereafter added to generate said high energy vapor within said second energy input zone which is utilized as aforesaid in step (5).
 6. communicating the increased energy level medium within said second energy input zone in a second fluid energy transmitting relationship with said energy conversion zone and causing flow of increased energy level medium out of said second energy input zone and flow of increased energy level medium into said energy conversion zone,
 7. converting within said energy conversion zone a portion of the energy of said increased energy level medium in said second fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said second fluid energy transmitting relationship,
 7. A process as defined in claim 1 wherein the heat added in obtaining said high energy vapor is created by continuously combusting fuel in the presence of an oxidant and confining the flow of the products of combustion along flow paths which include first and second heat exchange zones disposed in heat exchange relation with the fluid medium within said first and second energy input zones respectively.
 7. means for obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships.
 8. A process as defined in claim 7 wherein said high energy vapor is obtained by communicating a third heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone as aforesaid in step (4) so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said third heat exchange zone and by communicating a fourth heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone as aforesaid in step (8) so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said fourth heat exchange zone.
 8. communicating reduced energy level medium within said energy conversion zone with said first energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said first energy input zone, and
 9. obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to fluid medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships.
 9. A process as defined in claim 8 wherein the fluid medium flowing between said energy conversion zone and said third and fourth heat exchange zones is cooled.
 10. A process as defined in claim 7 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.
 11. A process as defined in claim 1 wherein said high energy vapor is obtained by communicating a first heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone as aforesaid in step (4) so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virTue of having passed through said first heat exchange zone and by communicating a second heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone as aforesaid in step (8) so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said second heat exchange zone.
 12. A process as defined in claim 1 wherein the fluid medium flowing out of said energy conversion zone and into said first and second energy input zones as aforesaid in steps (4) and (8) flows in heat exchange relation with the fluid medium in said first and second fluid energy transmitting relationships so that the fluid medium flowing into said energy input zones has an increased temperature energy level with respect to the associated fluid medium flowing out of said energy conversion zone.
 13. A process as defined in claim 12 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.
 14. A process as defined in claim 12 wherein said fluid medium is H2O and wherein the heat added in obtaining said high energy vapor is generated by combusting a hydrocarbon fuel with an oxidant, and wherein said high energy vapor is obtained by alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and then alternately communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones so as to enter therein as said high energy vapor.
 15. A process as defined in claim 1 wherein said high energy vapor is obtained by alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths, combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.
 16. A process as defined in claim 1 wherein said fluid medium is H2O and wherein the heat added in obtaining said high energy vapor is generated by combusting a hydrocarbon fuel with an oxidant, and wherein said high energy vapor is obtained by alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and then alternately communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones so as to enter therein as said high energy vapor.
 17. In a process for converting heat into work by repetitious cycles, each cycle of which includes the steps of utilizing a high enerGy gaseous vapor within a first energy input zone containing a portion of fluid medium at a low energy level to thereby increase the energy level of the fluid medium in said first energy input zone, communicating the increased energy level medium within said first energy input zone in a first fluid energy transmitting relationship with an energy conversion zone and causing flow of increased energy level medium out of said first energy input zone and flow of increased energy level medium into said energy conversion zone, converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said first fluid energy transmitting relationship, communicating reduced energy level medium within said energy conversion zone with a second energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said second energy input zone, utilizing a high energy gaseous vapor within said second energy input zone to thereby increase the energy level of the fluid medium in said second energy input zone, communicating the increased energy level medium within said second energy input zone in a second fluid energy transmitting relationship with said energy conversion zone and causing flow of increased energy level medium out of said second energy input zone and flow of increased energy level medium into said energy conversion zone, converting within said energy conversion zone a portion of the energy of said increased energy level medium in said second fluid energy transmitting relationship into work thereby reducing the energy level of the fluid medium in said second fluid energy transmitting relationship, and communicating reduced energy level medium within said energy conversion zone with said first energy input zone and causing reduced energy level medium to flow out of said energy conversion zone and fluid medium to flow into said first energy input zone, the improvement in combination therewith which comprises the step of obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to fluid medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships.
 18. Apparatus for converting heat into work by repetitious cycles which comprises
 19. Apparatus as defined in claim 18 wherein said high energy gaseous vapor obtaining means includes means defining a high energy medium storage zone, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with high energy medium in said storage zone to cause flow therein, means for alternately communicating the high energy medium in said storage zone with said first and second energy input zones, and means for adding heat to the high energy medium communicating between said storage zone and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.
 20. Apparatus as defined in claim 18 including means for communicating said second energy input zone with the atmosphere during the flow of fluid medium into said second energy input zone, and means for communicating said first energy input zone with the atmosphere during the flow of fluid medium into said first energy input zone.
 21. Apparatus as defined in claim 20 wherein said medium is a combustible material in the presence of an oxidant and means for combusting the fluid medium communicated with the atmosphere with an oxidant to provide the source of added heat.
 22. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second heat exchange zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, means for alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and means for adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.
 23. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining a first porous heat storage bed within said first energy input zone for which absorbing heat during the flow of medium into said first energy input zone, means for thereafter adding heat to said first porous heat storage bed to generate said high energy vapor within said first energy input zone, means defining a second porous heat storage bed within said second energy input zone for absorbing heat during the flow of medium into said second energy input zone, and means for thereafter adding heat to said second porous heat storage bed to generate said high energy vapor within said second energy input zone.
 24. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means for continuously combusting fuel in the presence of an oxidant and means for confining the flow of the products of combustion along flow paths which include first and second heat exchange zones disposed in heat exchange relation with the fluid medium within said first and second energy input zones respectively.
 25. Apparatus as defined in claim 24 wherein said high energy vapor obtaining means comprises means defining a third heat exchange zone disposed in heat exchange relation with a fluid medium in said second energy input zone meAns for communicating said third heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said third heat exchange zone, means defining a fourth heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone means for communicating said fourth heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said fourth heat exchange zone.
 26. Apparatus as defined in claim 25 including means for cooling the fluid medium flowing between said energy conversion zone and said third and fourth heat exchange zones.
 27. Apparatus as defined in claim 24 wherein said high energy vapor obtaining means includes means defining first and second heat exchange zones disposed in heat exchange relation with said first and second energy input zones, means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second heat exchange zones so as to cause flow of increased energy level medium alternately into said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones and increase the temperature of the fluid medium flowing out of said first and second heat exchange zones, means for alternately communicating the increased temperature energy level medium flowing from said first and second heat exchange zones with said first and second energy input zones and means for adding heat to the increased temperature energy level medium communicating between said first and second heat exchange zones and said first and second energy input zones so that the heated medium enters said first and second energy input zones as said high energy vapor.
 28. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining a first heat exchange zone disposed in heat exchange relation with the fluid medium in said second energy input zone means for communicating said first heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said second energy input zone so that the fluid medium flowing into said second energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said first heat exchange zone, means defining a second heat exchange zone disposed in heat exchange relation with the fluid medium in said first energy input zone and means for communicating said second heat exchange zone in series between the fluid medium flowing out of said energy conversion zone and into said first energy input zone so that the fluid medium flowing into said first energy input zone is at a temperature energy level greater than the fluid medium flowing out of said energy conversion zone by virtue of having passed through said second heat exchange zone.
 29. Apparatus as defined in claim 18 including means for confining the flow of the fluid medium out of said energy conversion zone and into said first and second energy input zones in heat exchange relation with the fluid medium in said first and second fluid energy transmitting relationships so that the fluid medium flowing into said energy input zones has an increased temperature energy level with respect to the associated fluid medium flowing out of said energy conversion zone.
 30. Apparatus as defined in claim 29 wHerein said high energy vapor obtaining means includes means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths, means for combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and means for directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.
 31. Apparatus as defined in claim 29 wherein said fluid medium is H2O and wherein said high energy vapor obtaining means includes means for combusting a hydrocarbon fuel with an oxidant, and means for alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and means for alternately communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones.
 32. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means for alternately communicating the increased energy level medium in said first and second fluid energy transmitting relationships with said first and second energy input zones along separate flow paths, combusting fuel with oxidant to add heat to said flow paths at combustion positions adjacent said energy input zones and directing the products of combustion in heat exchange relation along said paths so that the products of combustion having the highest temperature give up heat to the fluid medium in said flow paths nearest the combustion positions and the products of combustion having the lowest temperature give up heat to the fluid medium in said flow paths farthest from said combustion positions.
 33. Apparatus as defined in claim 18 wherein said fluid medium is H2O and wherein said high energy vapor obtaining means includes means for combusting a hydrocarbon fuel with an oxidant, and means for alternately communicating fluid medium in said first and second fluid energy transmitting relationships with the combusted oxidant and fuel to heat the medium and means for communicating the heated medium with the products of combustion in contact therewith with said first and second energy input zones so as to enter therein as said high energy vapor.
 34. Apparatus as defined in claim 18 wherein said means defining said first and second energy input zones comprises a pair of fluid pressure containers, each of said fluid pressure containers having a flexible diaphragm therein separating the interior thereof into a first portion containing all of the vapor fluid medium therein and a second portion containing only liquid fluid medium.
 35. Apparatus as defined in claim 18 wherein said high energy vapor obtaining means includes means defining a fluid medium heating zone, means for heating fluid medium in said heating zone, check valve operated means for alternately communicating fluid medium in said first and second fluid energy transmitting relationships with said heating zone, valve operated means disposed in parallel relation with respect to said check valve operated means for alternately communicating fluid medium in said first and second energy input zones with said heating zone, and means for alternately communicating the heated fluid medium in said heating zone with said first and second energy input zones.
 36. In apparatus for converting heat into work by repetitious cycles comprising means defining a first energy input zone within which a high energy gaseous vapor is utilized to increase the energy level of fluid medium at a low energy level therein, means defining A second energy input zone within which a high energy gaseous vapor is utilized to increase the energy level of the fluid medium at a low energy level therein, means defining an energy conversion zone, means for alternately communicating the increased energy level medium within said first and second energy input zones in first and second fluid energy transmitting relationships with said energy conversion zone and for causing flow of increased energy level medium out of said first and second energy input zones and flow of increased energy level medium in a liquid phase into said energy conversion zone, means for converting within said energy conversion zone a portion of the energy of said increased energy level medium in said first and second fluid energy transmitting relationships into work thereby reducing the energy level of said medium in said first and second energy transmitting relationships, and means for alternately communicating reduced energy level medium in a liquid phase within said energy conversion zone with said first and second energy input zones and for causing reduced energy level medium in a liquid phase to flow out of said energy conversion zone and reduced energy level medium to flow alternately into said first and second energy input zones, the improvement in combination therewith which comprises means for obtaining the high energy gaseous vapor utilized within said first and second energy input zones by adding heat to medium which has been energized by energy transfer with fluid medium in said first and second fluid energy transmitting relationships. 